Value Collection 101058PR Set Screw 3-48 X 1/8 in Cup Point

Product Description

The VALUE COLLECTION 101058PR is a Grade 8 alloy steel cup point set screw sized 3-48 x 1/8 inches overall length. Set screws are headless fasteners used to secure a component — such as a collar, gear, or pulley — against a shaft by bearing directly into the shaft surface. The cup point tip bites into the mating surface for firm, positive holding. Drive is internal hex (Allen key), requiring a 0.050-inch hex key for installation. Thread standard is UNC, conforming to ASME/ANSI B18.3 and ASTM F912. These fasteners are installed by machinists, millwrights, and maintenance technicians in mechanical assemblies requiring precise axial and rotational locking.

This set screw is suited for light-duty mechanical applications where a small-diameter, fine-thread fastener is needed to lock rotating or sliding components in position. The 3-48 UNC thread is among the smallest standard inch-series thread sizes and is common in instrument assemblies, small motors, miniature couplings, and precision equipment. The cup point profile distributes clamping force into a small contact area, providing reliable holding in both ferrous and non-ferrous shaft materials. These are sold individually but require a minimum order quantity of 100 pieces.

Key Features

• Grade 8 alloy steel construction for high tensile strength in a small form factor
• Cup point tip bites into shaft surface for positive, slip-resistant hold
• Internal hex (Allen) drive with 0.050-inch hex key size
• 3-48 UNC thread conforms to ASME/ANSI B18.3 and ASTM F912 standards
• Headless design allows full countersinking flush with or below the workpiece surface
• Fractional inch sizing — 1/8-inch overall length for compact assemblies

Compatibility

Designed as a standard UNC inch-series set screw for use in any mechanical assembly requiring a 3-48 threaded socket, including instrument enclosures, small-diameter shaft collars, miniature couplings, and precision equipment.

Installation Notes

Installation requires a 0.050-inch hex key (Allen wrench); use of an incorrectly sized key risks rounding the drive socket. Torque to the assembly specification for the application — do not overtighten, as small-diameter alloy set screws are susceptible to torsional fracture. Ensure the mating threaded hole is clean and free of debris before threading in. Where used in vibrating equipment, a thread-locking compound appropriate for the operating temperature may help prevent loosening.